Basically no one can do 60-minutes at FTP
In theory, 60-minutes is possible, but in reality almost no one will unless their FTP is set too low. W’Bal shows that it is “easy.” That is because W’Bal is not about easy or hard. It only looks at what is above FTP (anaerobic) and sees if it it is possible. Don’t use W’Bal for anything close to or below your FTP. See below. The cutoff of when it get’s useful is individual but I would say somewhere around 115% of FTP and above. It’s generally good for VO2max and above. W’ is not perfect, it’s just a starting point.